My friend and I both like the same boy.

It was around the second month of 9th grade when a new girl (A) joined our class. I had no friends, so I thought I'd get to know her, maybe she'd be on the same wavelength as me. I did, and she really seemed like a good match, but she seemed a bit arrogant. Then everyone started to hate her, and because of their influence, I felt that way too, so I distanced myself from her. Around that time, I got close to another girl (B). She was nice, but she was the type of person people couldn't refuse. When A saw that I was friends with B, she tried to get between us. Then, because B couldn't refuse anyone, she treated A well. We became a group of three friends. I warmed up to her, and we spent a lot of time together, becoming very close. Then one day, A and I met the same boy (K). It was like we both had a crush on him. At first, to avoid ruining our friendship, we agreed to talk to two girls from his class and a girl from our class. We lied and said that the girl liked him. The lie was about to be exposed, and it was. To avoid ruining our friendship, I told A that I had broken up with him because if I hadn't said that, A would have broken up with him. He would even open it and beat me up. Then we gave the kid his ***, but the kid never talks to him, he always says he's not available. They don't talk at school either. A doesn't know, but I'm on his *** account, and when I read his messages with his friends, he writes things like "I have a flirt," but K doesn't even care about him. The other day, some people I know from 11th grade came over; they know the whole thing, they know A. They told me, "I think you should break off your friendship with A. In this situation, both of us should have left the kid for the sake of our friendship," but I'm not very sure what to do. (The translation might be unclear, sorry.)